/Engine/Plugins/Runtime/GeometryProcessing/Source/DynamicMesh/Public/Operations/GroupTopologyDeformer.h
Populate the internal ROI data structures based on the given HandleGroups and ROIGroups. HandleGroups will be empty if the Handle is a set of Vertices or Edges.
virtual void CalculateROI ( const [TArray](API\Runtime\Core\Containers\TArray)< int > & HandleGroups, const [TArray](API\Runtime\Core\Containers\TArray)< int > & ROIGroups )